Wanawimol Saengchote M.D.
Department of Anesthesiology,
Ramathibodi Hospital, Mahidol U
SAFETY
Anesthesia Incident Monitoring Study
 January to June 2007.
 200,000 cases, 2537 incidents
 A standardized incident report form
was developed in order to fill in what,
where, when, how, and why it
happened

Arrhythmia 25%
 Desaturation 24%
 Death within 24 hrs. 20%
 Cardiac arrest 14%
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inexperience,
lack of vigilance,
inadequate preanesthetic evaluation,
inappropriate decision,
emergency condition,
haste,
inadequate supervision,
ineffective communication.
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DO2 = CO x 10 x CaO2
Tissue O2 delivery = cardiac output x arterial O2 content
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CO = SV x HR
SV ∞ preload, contractility, afterload
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CO = EF x LVEDV x SVR x HR
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Patient’s comorbid : controllability?
 Anesthetic management : drugs,
techniques, process, anesthesia
personnel
 Surgical procedure
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Hypovolemia
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Preop NPO
Trauma-fractures
Peritonitis
N/v, diarrhea
Bowel prep
Diuretics
Preoperative
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Blood loss
Major fluid shift
Tissue edema
Effusion
Diuresis
(concealed blood loss)
Intraoperative & PO.
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Tachycardia
Peripheral vasoconstriction
Low systolic blood pressure
Narrow pulse pressure
Cold ,clammy skin and extremities
Low urine output
(anemia not apparent in acute loss without
adequate volume replacement)
With beta blocker effect, no tachycardia
detected
Class I
Class II
Class III
Class IV
Pulse rate
<100/min
>100/min
>120/min
>140/min
BP
normal
normal
dropped
dropped
Pulse pr.
normal
decreased
decreased
decreased
RR
14-20/min
20-30/min
>30/min
>35/min
Urine
>30ml/hr
20-30ml/hr
5-15ml/hr
minimal
Capill.refil
normal
delayed
delayed
delayed
Mental st.
Sl.anxious
anxious
confused
lethargic
Bl.loss(ml.,%)
<750
<15%
750-1,500
15-30%
1,500-2,000
30-40%
>2,000
>40%
Fluid
crystalloid
+colloid
+colloid,bl.
+colloid,bl.
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Alert to environment, notice surgeon’s (and
team) expression
Good communication
Adequate volume loading is all the time
necessary (crystalloid – colloid)
Blood and blood component as required
Critical perfusion pressure should be
maintained (MAP > 65 mmHg)
Concern about distribution of regional blood
flow
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1. Drug effect : nearly all anesthetic agents
depress myocardial contractility
Potent inhalation agents
Nitrous oxide in compromised heart
Intravenous : thiopental , propofol, ketamine
Opioid : pethidine
( arrhythmogenic effect to be discussed later)
Coronary artery disease
 Myocardial ischemia / infarct
 Cardiogenic shock
Valvular heart disease
 Congestive heart failure
most common rheumatic heart disease :
mitral, aortic , tricuspid valve
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Acute ischemic episode  large or significant
myocardial loss ⇨ serious ventricular
arrhythmia, pulmonary congestion ,
hypotension ..... Hemodynamic support :
inotropes , antiarrhythmic , mechanical
device
Cardiac markers : troponin I, AST, LDH, CKMB
cTnT < 0.1 ng/L, cTnI < 2.0 ng/L, CK-MB
0-25 u/L ( > 2 x normal)
Obstruction to heart, cardiac chambers or
great vessels  reduced stroke volume
Causes :
1.Cardiac tamponade from injury, post cardiac
surgery, cardiac catheterization *
2.Tension pneumothorax *
3. Pulmonary embolism *
4. Surgical manipulation in chest, esophageal,
cardiac surgery
5. Supine hypotensive syndrome
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1. drug interactions : concurrent drug use +
anesthetic effect
ACEI, CCB, opioids, IV anesthetic, inhalation
agent
 2. regional anesthesia : spinal, epidural an.
with sympathetic blockade effect
 3. various drug effect : antibiotics, protamine,
 4. bone cement
 5. sepsis, adrenal insufficiency, blood
transfusion
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20% of population with hypertensive diseases
 Causes of intraoperative HTN
1. Response to laryngoscopy and intubation
2. Light anesthesia
3. Hypercarbia
4. Hypoxemia
5. Drug effect
6. Hypervolemia
7. Specific surgical procedure
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Causes of HTN postop and at emergence
1. Stimuli from endotracheal & extubation
2. Pain
3. Hypoventilation, airway obstruction
4. Hypothermia,shivering
5. Acidosis
6. Full bladder
7. Antihypertensive withdrawal
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Risk Factors
1. Hypertension
2. Diabetes mellitus
3. Underlying heart disease : CAD, VHD
4. Liver disease, renal disease
5. Head injury
6. Sepsis
7. Carbon monoxide poisoning
(elderly, malnutrition, hypoalbuminemia)
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A 62 yr-old female suspected CBD stone,
scheduled for ERCP , plan for post procedural
admission.
Anesthetic time 1 hr 15 mins. ,uneventful an.
and surgical procedure
After extubation, ? Abn. breathing pattern,
occ. fine crepitations BLL. Later SPO2 drop
IV fluid 800 mL, minimal blood loss
Diuretic given, PACU > 2 hrs.
At ward SBP drop, intubate –ventilate,on dopa
1. Physiological disturbances during anesthesia
Anesthetics modify body mechanism + vagal
dominant, acidosis, hypoxia/ hypercarbia,
electrolyte disorder, hypovolemia
2. Pathological disturbances
CAD : heart block, PVC,
Thyrotoxicosis, MH, pheochromocytoma
3. Pharmacological causes :ketamine, NMB
4. Anesthesia procedures : IT, CVP, SA
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Serious cardiac
♥arrhythmia :
6H, 5T
Hypovolemia,
hypoxemia,
acidosis, K- Ca
hypothermia, PE,
♥ tamponade
tension
pneumothorax
Know how, Know why, Care why